Los Angeles → Seoul

Autumn, September to November, is the season most worth structuring a long trip around. Seoul's foliage runs across the hills and palace grounds, the skies clear, temperatures settle at 15–22°C, and the festival calendar is at its fullest. For anyone spending real money and real vacation days, it is the highest-return window.

Spring, March to May, is the other marquee season, defined by cherry blossom that usually peaks in early April. The weather is comfortable and Seoul's parks look their best. Because the bloom is short and the demand international, this is the window where booking late hurts most — decide early if the blossom is the point of the trip.

Winter, December to February, is cold at roughly -5 to 5°C, which is a serious adjustment from a Los Angeles winter. The trade-off is real: ski season, winter festivals, and the cheapest flights of the year, which on a long-haul route is a meaningful difference. If you can dress for it, winter is the value play.

Seoul runs on UTC+9, and flying west across the Pacific you cross the international date line, so you land on a later calendar day than you departed — build a slow first day into the plan and expect jet lag to be the real cost of this route. The return direction usually feels easier.

South Korea uses the Korean Won (KRW), and the language is Korean. English signage is dependable in the subway and at major sights but thins out quickly in neighbourhood restaurants, so a translation app earns its place next to your maps app.

That maps app should be Naver Maps, not Google Maps, which does not function properly in South Korea because of national security restrictions on mapping data — a surprise that catches many first-time visitors from the US. For transport, buy a T-money card at any convenience store: it covers all buses, the entire subway and even some taxis. On entry documents, note that Vietnamese passport holders require a K-ETA electronic travel authorisation submitted online at least 72 hours before departure, and you should always confirm the rules that apply to your own passport.

Seoul's neighbourhoods divide fairly clearly. Hongdae is the budget and nightlife base around the university district, good for younger travellers and long-stay visitors. Myeongdong is mid-range and central for shopping. Gangnam and Apgujeong hold the luxury hotels and designer streets, and suit travellers who want a quieter, more polished base after a long flight.

On a longer trip you can take the sights slowly: Gyeongbokgung Palace and the traditional lanes of Bukchon Hanok Village in one unhurried block, N Seoul Tower on Namsan for the panorama on a clear evening, and Korean BBQ in Mapo-gu on a night you have no early start.

Do not underestimate convenience stores either — CU and GS25 sell hot kimbap, ramyeon and rice bowls that function as full meals, which is genuinely useful when jet lag has you awake and hungry at odd hours. For neighbourhood-by-neighbourhood detail, transport advice and where to eat, see our destination guide at /en/destinations/seoul.